Resolvesbigdatagenomics#1964. There was an underflow somewhere causing round trip from
log space values to Phred to mismatch for values between 164 and 254.
This change lowers the point where we switch from using the precomputed
table to where we use the log math. Also, we add a unit test checking
round trip values using PhredUtils.

Resolvesbigdatagenomics#1964. There was an underflow somewhere causing round trip from
log space values to Phred to mismatch for values between 164 and 254.
This change lowers the point where we switch from using the precomputed
table to where we use the log math. Also, we add a unit test checking
round trip values using PhredUtils.

Resolvesbigdatagenomics#1964. There was an underflow somewhere causing round trip from
log space values to Phred to mismatch for values between 164 and 254.
This change lowers the point where we switch from using the precomputed
table to where we use the log math. Also, we add a unit test checking
round trip values using PhredUtils.

Resolves#1964. There was an underflow somewhere causing round trip from
log space values to Phred to mismatch for values between 164 and 254.
This change lowers the point where we switch from using the precomputed
table to where we use the log math. Also, we add a unit test checking
round trip values using PhredUtils.